Methods of manufacture and use of energized ophthalmic devices having an electrical storage mode

ABSTRACT

This invention discloses methods of manufacture and use of an energized Ophthalmic Device with an incorporated Storage Mode for a power source, the method of manufacturing said device, and a method of activation that may restore the power source to an operational mode.

RELATED APPLICATIONS

This application claims priority as a Continuation in Part PatentApplication to patent application Ser. No. 13/781,494, filed Feb. 28,2013, a U.S. Non-Provisional Patent Application entitled Methods AndApparatus To Form Electronic Circuitry on Ophthalmic Devices whichclaims priority to Provisional Patent Application No. 61/604206,entitled Methods And Apparatus To Form Electronic Circuitry onOphthalmic Devices on Feb. 28, 2012.

FIELD OF USE

This invention describes the methods of manufacture and use of anenergized Ophthalmic Device with a Media Insert with a Storage Mode, andmore specifically, where the Media Insert incorporates a SwitchingMechanism that may be placed in a Storage Mode and in an Operating Mode.

BACKGROUND

Traditionally, an Ophthalmic Device, such as a contact lens, anintraocular lens, or a punctal plug, included a biocompatible devicewith a corrective, cosmetic, or therapeutic quality. A contact lens, forexample, may provide one or more of vision correcting functionality,cosmetic enhancement, and therapeutic effects. Each function is providedby a physical characteristic of the lens. A design incorporating arefractive quality into a lens may provide a vision corrective function.A pigment incorporated into the lens may provide a cosmetic enhancement.An active agent incorporated into a lens may provide a therapeuticfunctionality. Such physical characteristics are accomplished withoutthe lens entering into an energized state. A punctal plug hastraditionally been a passive device.

More recently, active components have been incorporated into a contactlens. Some components may include semiconductor devices. Some exampleshave shown semiconductor devices incorporated in a contact lens placedupon animal eyes. It has also been described how the active componentsmay be energized and activated in numerous manners within the lensstructure itself The topology and size of the space defined by the lensstructure creates a novel and challenging environment for the definitionof various functionalities. It is important to provide reliable,compact, and cost effective means to interconnect and attach thecomponents upon form factors consistent with the ophthalmic environment.

Including energization elements in an Ophthalmic Device adds the issueof loss of energization between the manufacturing date and the date ofactual use of the device. One of the more significant causes of loss ofenergization may be the leakage of electrical current through devicesand structures that connect physically and electrically with theenergization elements. Many Ophthalmic Devices, such as disposablecontact lenses, have typical shelf lives of six years; hence, there is aneed to minimize energization losses by ensuring extremely low leakagecurrent. Therefore, it may be important to ensure that includedenergization elements and the electrical components they connect to havevery low leakages and designed modes of operation that minimize the lossof energization during storage periods. Incorporating the energizationelements into the Ophthalmic Device presents the additional issue tocurrent leakage because the solutions to the leakage cannot depend ondirect electrical contact.

Technological embodiments that address such an ophthalmologicalbackground need may generate solutions that not only address ophthalmicrequirements but also encompass novel embodiments for the more generaltechnology space defining energy conservation for encapsulated energizedelements.

SUMMARY

Accordingly, the present invention includes an encapsulated Media Insertwith a Storage Mode that may be included into an energized OphthalmicDevice, and in some embodiments, specifically, a contact lens. StorageMode reduces leakage within the Media Insert while operating levels ofcurrent are not required. In some embodiments, an energized OphthalmicDevice with a Storage Mode is provided.

The present invention therefore includes disclosure of a SwitchingMechanism with a Storage Mode and an Operating Mode, wherein theSwitching Mechanism is incorporated into a circuit with at least a loadand a power source. For example, the load may control a specificfunction of the device, such as, for example, optic power adjustment, oradministration of an active agent. The circuit may be included in anencapsulated Media Insert that may be included in an energizedOphthalmic Device.

The Media Insert may be fully encapsulated to protect and contain theenergization elements, traces, and electronic components. The OphthalmicDevice, which may be comprised of a polymeric biocompatible material,may include a rigid center, soft skirt design wherein a central rigidoptical element comprises the Media Insert.

In some embodiments, a Storage Mode may be modeled to occur when theSwitching Mechanism is modeled to have an increased resistance resultingin a reduced leakage current. This leakage current may meet desiredStorage Mode current consumption specifications, and therefore may allowfor a substantial shelf life of the energized Ophthalmic Device. Becausethe Media Insert is fully encapsulated, the Switching Mechanism may beresponsive to an outside stimulus that may originate outside the devicewhile not in direct contact with the circuit. Thus, the SwitchingMechanism 315 may also be comprised of sensor portions of various kinds.For example, these sensors may be antennas to receive and react to radiofrequency emissions as the stimulus, or they may be photocells to reactto photon-based outside stimulus.

To further conserve energy, even when the Ophthalmic Device is not in aStorage Mode, a Sleep Mode may be combined with a Storage Mode function.Whereas a Storage Mode may typically refer to a low energy consumptivestate that involves a Switching Mechanism introducing a high resistanceinto the conductive path of the power source to the load, a Sleep Modemay refer to a low energy consumptive status of electronic circuitrywhen that circuitry is connected via a low resistance path to the powersource.

In some embodiments, a Reset Function may be triggered during thetesting process prior to packaging or during the assembly of componentsthemselves. For example, the Reset Function may establish an optimumresting state of the circuit if the device is put into Storage Mode aspecified time later. In some embodiments, a block of electroniccircuitry may be able to perform the Reset Function and place at least aportion of the load in a predefined energized state.

The methods of including a Media Insert with a Storage Mode in anencapsulated Ophthalmic Device may also be significant. Accordingly,methods of manufacture are described herein. In some embodiments, a loadthat may operate within an energized Ophthalmic Device may beincorporated in the Media Insert in a circuit with the power source anda Switching Mechanism. In some such embodiments, a reset function may beintegrated with the circuit. During the manufacturing process, theenergized Media Insert may be placed in a Storage Mode. Some embodimentsmay include an assembly testing process, wherein the Media Insert may betaken out of Storage Mode to evaluate the operation of the OphthalmicDevice and subsequently returned to Storage Mode. The Ophthalmic Devicemay be optionally placed in a sealed package that may preventunintentional activation of the Ophthalmic Device from a Storage Modeprior to user activation. This method of manufacture may be useful inembodiments where the Media Insert is encapsulated in an energizeddevice other than an Ophthalmic Device.

The methods of using an encapsulated Ophthalmic Device with a MediaInsert with a Storage Mode may be significant. Accordingly, methods ofuse are described herein. In some embodiments, a user may open a sealedpackage, such as a blister, that contains an energized Ophthalmic Devicein a Storage Mode, and an outside stimulus may wake the device from aStorage Mode by triggering the Switching Mechanism. In some specificembodiments, the user may directly trigger the Switching Mechanism, suchas, for example, in a mechanical system, the outside stimulus may bepressure on the Switching Mechanism, requiring the user to squeeze orpinch the device. In other embodiments, the removal of the OphthalmicDevice may expose the Switching Mechanism to the appropriate outsidestimulus and thereby may not require additional action from the user.

In embodiments where an Ophthalmic Device may be used multiple times,further steps may be required. In such embodiments, conserving currentleakage during storage periods between usages may allow for extendedpower supply life. Accordingly, a user may be able to return theOphthalmic Device to a Storage Mode and store the Ophthalmic Deviceuntil it is needed for a subsequent use. This method of use may beuseful in embodiments where the Media Insert is encapsulated in anenergized device other than an Ophthalmic Device.

DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary embodiment of a Media Insert for anenergized

Ophthalmic Device and an exemplary embodiment of an energized OphthalmicDevice.

FIG. 2 illustrates a model for the mechanisms of energization loss fordevices with energization elements or Power Sources.

FIG. 3 illustrates an exemplary embodiment of a circuit design for anenergized device with an externally activated Storage Mode, which may beuseful in Ophthalmic Devices with encapsulated Media Inserts.

FIG. 4 illustrates alternate embodiments of circuit designs forenergized devices with externally activated Storage Modes, which may beuseful in Ophthalmic Devices with encapsulated Media Inserts.

FIG. 5 illustrates an exemplary embodiment of a circuit design for anenergized device with a Storage Mode wherein a Switching Mechanismimportant to the state of the Storage Mode is itself comprised of aseparate load and switch, which may be useful in Ophthalmic Devices withencapsulated Media Inserts.

FIG. 6 illustrates a flowchart for an exemplary process formanufacturing an energized Ophthalmic Device with a Storage Mode.

FIG. 7 illustrates a flowchart for an exemplary process for using anenergized Ophthalmic Device with a Storage Mode.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to an energized Ophthalmic Device having aStorage Mode that may conserve energy by reducing current Leakage whenthe Ophthalmic Device is not being used, and the invention furtherincludes the methods of manufacture and use. In the following sectionsdetailed descriptions of embodiments of the invention will be given. Thedescription of both preferred and alternative embodiments are exemplaryembodiments only, and it is understood that to those skilled in the artthat variations, modifications and alterations may be apparent. It istherefore to be understood that said exemplary embodiments do not limitthe scope of the underlying invention.

An incorporated battery may have a low-leakage state or Storage Mode tomaintain enough power to be operational upon use of the OphthalmicDevice. The user of the Ophthalmic Device may then be able to activateor wake up the battery and/or load circuit. Power sources with a StorageMode may already exist in the electronics field to minimize leakageprior to use of the device, but the issues involved with an energizedOphthalmic Device are distinct from those products currently available.For instance, a common technique in toys to preserve power is to packagethe product with paper used to cover a coin cell battery. Upon pulling atab, the paper is removed and contact is made between the battery andcircuit. Prior to such activation, the system is in a low-leakage statewith long shelf life. Such methods cannot be used for an electronicsystem encapsulated within a contact lens.

Incorporating the energization elements into the Ophthalmic Devicepresents additional issues to current leakage because the solutions tothe leakage may not depend on direct electrical contact. Therefore, themethods of activation may rely on an outside stimulus whereas themechanism for switching from storage to active mode could be containedwithin the energized Ophthalmic Device. This concept is similar to thatof a “glow stick” where energy (in the case of a glow stick, a chemicalreaction that creates light) is not released until a purposeful event(snapping the slick) activates the device. Unlike a glow stick, anenergized Ophthalmic Device with an encapsulated Media Insert maycontain complex electronic components and may comprise biocompatiblematerial.

The small space within an ophthalmic Media Insert may add anotherlimitation to a Storage Mode. The area in an ophthalmic Media Insert forall the components of the circuitry including the Switching Mechanismmay be 1.5 square millimeters. Size restrictions also limit the possiblepower supply, and the area used by circuitry may subtract from the areaavailable for the power supply. Accordingly, the range of allowableleakage wherein the energized Ophthalmic Device may still function forpractical use after shelf life is very small. The present inventionaddresses this issue of energy conservation.

Glossary

In this description and claims directed to the presented invention,various terms may be used for which the following definitions willapply:

Encapsulate: as used herein refers to creating a barrier to separate anentity, such as, for example, a Media Insert, from an environmentadjacent to the entity.

Energized: as used herein refers to the state of being able to supplyelectrical current to or to have electrical energy stored within.

Energy: as used herein refers to the capacity of a physical system to dowork. Many uses within this invention may relate to the said capacitybeing able to perform electrical actions in doing work.

Energy Source: as used herein refers to a device or layer that iscapable of supplying Energy or placing a logical or electrical device inan Energized state.

Energy Harvester: as used herein refers to a device capable ofextracting energy from the environment and converting it to electricalenergy.

Functionalized: as used herein refers to making a layer or device ableto perform a function including for example, energization, activation,or control.

Leakage: as used herein refers to unwanted loss of energy.

Lens or Ophthalmic Device: as used herein refers to any device thatresides in or on the eye. These devices may provide optical correction,may be cosmetic, or may provide functionality unrelated to the eye. Forexample, the term lens may refer to a contact lens, intraocular lens,overlay lens, ocular insert, optical insert, or other similar devicethrough which vision is corrected or modified, or through which eyephysiology is cosmetically enhanced (e.g. iris color) without impedingvision. Alternatively, the Lens may provide non-optic functions such as,for example, monitoring glucose or administrating an active agent. Insome embodiments, the preferred lenses of the invention are soft contactlenses are made from silicone elastomers or hydrogels, which include,for example, silicone hydrogels, and fluorohydrogels.

Lens-forming Mixture or Reactive Mixture or Reactive Monomer Mixture(RMM): as used herein refers to a monomer or prepolymer material thatmay be cured and cross-linked or cross-linked to form an OphthalmicDevice. Various embodiments may include Lens-forming Mixtures with oneor more additives such as, for example, UV blockers, tints,photoinitiators or catalysts, and other additives one might desire in anOphthalmic Devices such as, contact or intraocular lenses.

Lens-forming Surface: as used herein refers to a surface that is used tomold a lens. In some embodiments, any such surface can have an opticalquality surface finish, which indicates that it is sufficiently smoothand formed so that a lens surface fashioned by the polymerization of alens forming material in contact with the molding surface is opticallyacceptable. Further, in some embodiments, the Lens-forming Surface canhave a geometry that is necessary to impart to the lens surface thedesired optical characteristics, including without limitation,spherical, aspherical and cylinder power, wave front aberrationcorrection, corneal topography correction and the like as well as anycombinations thereof.

Lithium Ion Cell: as used herein refers to an electrochemical cell whereLithium ions move through the cell to generate electrical energy. Thiselectrochemical cell, typically called a battery, may be reenergized orrecharged in its typical forms.

Media Insert: as used herein refers to an encapsulated insert that willbe included in an energized Ophthalmic Device. The energization elementsand circuitry may be incorporated in the Media Insert. The Media Insertdefines the primary purpose of the energized Ophthalmic Device. Forexample, in embodiments where the energized Ophthalmic Device allows theuser to adjust the optic power, the Media Insert may includeenergization elements that control a liquid meniscus portion in theOptical Zone. Alternatively, a Media Insert may be annular so that theOptical Zone is void of material. In such embodiments, the energizedfunction of the Lens may not be optic quality but may be, for example,monitoring glucose or administering an active agent.

Mold: as used herein refers to a rigid or semi-rigid object that may beused to form lenses from uncured formulations. Some preferred Moldsinclude two Mold parts forming a front curve Mold part and a back curveMold part.

Operating Mode: as used herein refers to a high current draw state wherethe current over a circuit allows the device to perform its primaryenergized function.

Optical Zone: as used herein refers to an area of an Ophthalmic Devicethrough which a wearer of the Ophthalmic Device sees.

Power: as used herein refers to work done or energy transferred per unitof time.

Rechargeable or Re-energizable: as used herein refers to a capability ofbeing restored to a state with higher capacity to do work. Many useswithin this invention may relate to the capability of being restoredwith the ability to flow electrical current at a certain rate and for acertain, reestablished time period.

Reenergize or Recharge: as used herein refers to restoring to a statewith higher capacity to do work. Many uses within this invention mayrelate to restoring a device to the capability to flow electricalcurrent at a certain rate and for a certain, reestablished time period.

Reference: as use herein refers to a circuit that produces a fixed andstable voltage or current output suitable for use in other circuits. Areference may be derived from a bandgap, may be compensated fortemperature, supply, and process variation, and may be tailoredspecifically to a particular application-specific integrated circuit(ASIC).

Released from a Mold: as used herein refers to a lens that is eithercompletely separated from the Mold, or is only loosely attached so thatit may be removed with mild agitation or pushed off with a swab.

Reset Function: as used herein refers to a self-triggering algorithmicmechanism to set a circuit to a specific predetermined state, including,for example, logic state or an energization state. A Reset Function mayinclude, for example, a power-on reset circuit, which may work inconjunction with the Switching Mechanism to ensure proper bring-up ofthe chip, both on initial connection to the power source and on wakeupfrom Storage Mode.

Sleep Mode or Standby Mode: as used herein refers to a low current drawstate of an energized device after the Switching Mechanism has beenclosed that allows for energy conservation when Operating Mode is notrequired.

Stacked: as used herein means to place at least two component layers inproximity to each other such that at least a portion of one surface ofone of the layers contacts a first surface of a second layer. In someembodiments, a film, whether for adhesion or other functions may residebetween the two layers that are in contact with each other through saidfilm.

Stacked Integrated Component Devices or SIC Devices: as used hereinrefers to the products of packaging technologies that assemble thinlayers of substrates that may contain electrical and electromechanicaldevices into operative-integrated devices by means of stacking at leasta portion of each layer upon each other. The layers may comprisecomponent devices of various types, materials, shapes, and sizes.Furthermore, the layers may be made of various device productiontechnologies to fit and assume various contours.

Storage Mode: as used herein refers to a state of a system comprisingelectronic components where a power source is supplying or is requiredto supply a minimal designed load current. This term is notinterchangeable with Standby Mode.

Substrate Insert: as used herein refers to a formable or rigid substratecapable of supporting an Energy Source within an Ophthalmic Device. Insome embodiments, the Substrate insert also supports one or morecomponents.

Switching Mechanism: as used herein refers to a component integratedwith the circuit providing various levels of resistance that may beresponsive to an outside stimulus, which is independent of theOphthalmic Device.

Energized Ophthalmic Device

Proceeding to FIG. 1, an exemplary embodiment of a Media Insert 100 foran energized Ophthalmic Device and a corresponding energized OphthalmicDevice 150 are illustrated. The Media Insert 100 may comprise an OpticalZone 120 that may or may not be functional to provide vision correction.Where the energized function of the Ophthalmic Device is unrelated tovision, the Optical Zone 120 of the Media Insert 100 may be void ofmaterial. In some embodiments, the Media Insert 100 may include aportion not in the Optical Zone 120 comprising a substrate 115incorporated with energization elements 110 and electronic components105.

In some embodiments, a power source 110, which may be, for example, abattery, and a load 105, which may be, for example, a semiconductor die,may be attached to the substrate 115. Conductive traces 125 and 130 mayelectrically interconnect the electronic components 105 and theenergization elements 110. The Media Insert 100 may be fullyencapsulated to protect and contain the energization elements 110,traces 125 and 130, and electronic components 105. In some embodiments,the encapsulating material may be semi-permeable, for example, toprevent specific substances, such as water, from entering the MediaInsert 100 and to allow specific substances, such as ambient gasses orthe byproducts of reactions within energization elements, to penetrateor escape from the Media Insert 100.

In some embodiments, the Media Insert 100 may be included in anOphthalmic Device 150, which may comprise a polymeric biocompatiblematerial. The Ophthalmic Device 150 may include a rigid center, softskirt design wherein a central rigid optical element comprises the MediaInsert 100. In some specific embodiments, the Media Insert 100 may be indirect contact with the atmosphere and the corneal surface on respectiveanterior and posterior surfaces, or alternatively, the Media Insert 100may be encapsulated in the Ophthalmic Device 150. The periphery 155 ofthe Ophthalmic Device 150 may be a soft skirt material, including, forexample, a hydrogel material.

Proceeding to FIG. 2, a general model for circuit design aspectsimportant in relation to conserving power in energized devices, whichmay include energized Ophthalmic Devices, is illustrated. Ideally, whenthe device is in an Operating Mode, the power source 210 may supply theload 220 with full current and without any loss of current to otherpaths. In realistic conditions however, there are typically parallelleakage paths that may occur in devices, such as, for example, due toleakage within the power source itself or leakage along theinterconnections between the power source 210 and the load components220. The paths of these leakage currents may be modeled as a parallel“Shunt resistance” as shown as a shunt resistor 215. To the extentpossible, the leakage paths in the devices are minimized, which wouldcorrespond to a model with maximized values of the “Shunt Resistance.”Accordingly, preferable embodiments with low leakage may be modeled tohave a shunt resistor 225 with very high resistance, such as, forexample, 10⁹ ohms.

Even in embodiments where the shunt resistance is very high (and infollowing discussions assumed to be infinite where the shunt resistor isnot included in the circuit illustration), the power source may stillhave energy drawn from it through the load itself In some embodiments, aStorage Mode may be modeled to occur when the Switching Mechanism 205 ismodeled to have a varying resistance. In ideal cases, the resistanceacross the Switching Mechanism 205 may be zero when the circuit 225 isin an Operating Mode and infinite when the circuit 225 is in a StorageMode. In some exemplary embodiments, the Switching Mechanism may addminimal resistance, such as, for example, less than 10 ohms, when theSwitching Mechanism 205 is closed, and add very high resistance, suchas, for example, 10⁹ ohms, when the Switching Mechanism 205 is open. Insome embodiments, to meet this specification, the circuit may beinactive in a Storage Mode. For example, some embodiments may include ahigh-isolation switch that may shut the battery off from the load, wherethe load may include, for example, a reference, oscillators, a digitallogic circuits, or in some embodiments a lens driver circuit.

In an energized Ophthalmic Device, the load 220 may control a specificfunction of the device, such as, for example, optic power adjustment, oradministration of active agents. In some preferable embodiments, theload resistance may be nominal. The previously described examples forcurrent, power, and resistance may be within the normal operatingboundaries that apply in some exemplary embodiments. For example, insome preferable embodiments, the current draw when the energizedOphthalmic Device is in a Storage Mode, which may be classified as theleakage current, may be less than 400 pA.

This leakage current may meet desired Storage Mode current consumptionspecifications and therefore may allow for a substantial shelf life ofthe energized Ophthalmic Device. In some embodiments, for example, thelevel of leakage while the Ophthalmic Device is in a Storage Mode may beat a targeted level, which may give an added benefit of limiting thewear on the components of the circuit.

In some preferable embodiments, when the energized Ophthalmic Device isin an operating mode, the current may be 3 uA or less on average but maycontain peaks to 10 milliamps or more. I_(OPERATING MODE) may be thecurrent after the energized Ophthalmic Device has been woken up fromstorage, and I_(STORAGE MODE) may be the non-operating leakage currentwhile the device is in Storage Mode and may directly affect thepotential time the device may operate at its I_(OPERATING MODE).

In energized Ophthalmic Devices that do not have a Storage Mode, theavailable power from the energization elements after years of storagemight steadily decrease, potentially to a de-energized state of zeroavailable power. By adding a Storage Mode aspect to components or to thedevice design, the resulting device may be modeled as having a SwitchingMechanism 205 with a high R_(SWITCH OPEN) that may mitigate the currentloss over time. The time at which an active circuit may operate at agiven I_(OPERATING MODE) may be directly related to the R_(SWITCH OPEN)of the model Switching Mechanism 205 in that a higher R_(SWITCH OPEN)may reduce the leakage draw on the energization element, which may thenallow for a longer time that the device may operate at itsI_(OPERATING MODE). In another sense, when the device is operating itmay be important that the current flowing through the modeled SwitchingMechanism not cause effects within that mechanism itself; therefore, insome embodiments, the Switching Mechanism 205 may be comprised of amaterial that, when closed, may withstand currents up to and includingthe I_(OPERATING MODE) over the expected periods of operation.

There may be a variety of design parameters that relate to the type,dimension, and quantity of energization cells that are utilized for aparticular application. In some embodiments, for example, the powersource 210 may be comprised of two battery cells in series each having acell voltage of between 0.8 to 1.65V thus providing a voltage supply of1.6 to 3.3V. The desire to configure cells of this type into thisvoltage range may be related to the technology that is utilized in theelectronic circuitry as it may operate in a window around thiselectrical potential. If different types of battery are used, forexample, where the chemistry involved in the anodes and cathodes isvaried, the nominal cell voltages may shift.

Within a certain battery type, the size of the batteries employed may berelated to the electrical current phenomena that have been discussedherein. For example, a particular application may have a targetedoperating life at a certain operating current. Based on this targetvalue alone, the size requirements of the cells may simply be estimatedfrom the inherent energy density of the cells and the required energyfor the operating life. However, as has been described herein, thesituation may typically be more complicated since the energy requiredfor the storage life might also factor into the size requirement of thecells as well. The energy required for storage life is a significantfunction of I_(STORAGE MODE). Thus, it may be clear why minimization ofI_(STORAGE MODE) is desirable because it either reduces the amount ofbattery chemicals required for an application, or on the other hand,increases the operating life parameters for a given size of availablespace for batteries in an application.

By reducing leakage and limiting the energy flow through the circuit, aStorage Mode may also minimize the byproducts that may result fromreactions caused by an energized circuit. This may be particularlysignificant in embodiments where the Ophthalmic Device is shipped insmall, sealed packages, such as, for example, blisters, where even asmall accumulation of byproducts may be damaging to the integrity of theOphthalmic Device.

To further conserve energy, even when the Ophthalmic Device is not in aStorage Mode, a Sleep Mode may be combined with a Storage Mode function.Whereas a Storage Mode may typically refer to a low energy consumptivestate that involves a Switching Mechanism introducing a high resistanceinto the conductive path of the power source to the load, a Sleep Modemay refer to a low energy consumptive status of electronic circuitrywhen that circuitry is connected via a low resistance path to the powersource. Such a Sleep Mode may occur when the connected electroniccircuitry controls itself to essentially “turn off” most of itscircuitry, for example to save energy by waiting to perform sensorsampling at a predetermined rate.

Proceeding to FIG. 3, an exemplary embodiment of a circuit design for adevice with a Storage Mode is illustrated. The circuit 325 may include apower source 310 and a load 320 that may control a specific function ofthe Ophthalmic Device. As mentioned previously, the parasitic leakagesof the power source 310 itself and of the connections between the powersource 310 and the load 320 may be designed and manufactured to be verysmall and thus no “shunt resistance” is depicted for example. In someembodiments, a Switching Mechanism may be placed in series with thepower source 310 and the load 320 to facilitate a storage mode.

The Switching Mechanism 315 may be responsive to an outside stimulus 330not in direct contact at its origination with the circuit 325. TheSwitching Mechanism 315 is depicted generally as a device that issensitive and reactive to the outside stimulus 330. Thus, the SwitchingMechanism 315 may also be comprised of sensor portions of various kinds.For example, these sensors may be antennas to receive and react to radiofrequency emissions as the stimulus, or they may be photocells to reactto photon-based outside stimulus. There may be numerous types of sensorsinherent to a switch being sensitive to an outside stimulus. In otherembodiments, the detection of the outside stimulus may involve aphysical change of some kind to an element in the switch. For example,exposure of elements in the switch to a thermal stimulus from outsidethe lens may physically change the resistivity of a component within theswitch and cause a reaction much as the other described sensor elementscould. Some embodiments may be sensitive to sound as well.

In some embodiments, for example, control of the Switching Mechanism 315may use electronic means, mechanical means, or magnetic means. Forexample, electronic means may involve transistor circuitry in theswitching, mechanical means may involve metallic contacts in theswitching, and magnetic means may involve reed relays. There may benumerous switches that will have high resistance when in an off mode andlow resistance in an on mode.

Some embodiments may include a Switching Mechanism 315 that mayrepeatedly be placed in a Storage Mode and an Operating Mode, which mayallow, for example, testing during manufacturing or repeated use of theOphthalmic Device. In some such embodiments, the load 320 may alsocontrol the Switching Mechanism 315, allowing the load 320 to place theSwitching Mechanism 315 back into a Storage Mode. The load 320 maycontain additional sensors, such as, for example, an infrared link,which may receive commands from a user or some other passive outsidestimulus. Upon reception of a shutdown command, the load 320 mayactivate the Switching Mechanism.

In some embodiments, for example, the circuit may be comprised ofmultiple Switching Mechanisms, not shown, that may independently beactivated for a single use, which may allow for a specific number ofuses. In such embodiments, after a single use, a component, such as theload, may place one of the Switching Mechanisms into Storage Mode sothat the Ophthalmic Device may be activated again with minimal leakagewhile not in use. Where the circuit comprises multiple single-useSwitching Mechanisms, after the first use, the component may trigger asecond Switching Mechanism into Storage Mode, allowing that secondSwitching Mechanism to respond to an outside stimulus. In suchembodiments, the uses may be limited by the number of SwitchingMechanisms. In some alternative embodiments, such as with single dailyuse devices, the Switching Mechanism may be placed in a Storage Mode andactivated to an Operating Mode one time.

A Storage Mode may allow for reliable shipping methods because theOphthalmic Device may be kept in a known off state. In some embodiments,a Storage Mode alone may be sufficient in establishing a stable statefor shipping. In other alternative embodiments, a Reset Function may betriggered during the testing process prior to packaging or during theinitial assembly of the components into the device. For example, theReset Function may establish an optimum resting state of the circuit ifthe device is put into Storage Mode a specified time later. In someembodiments, this specified time may be shorter after testing than afteruser activation thereby allowing two Reset Functions, one for shippingand one for use. In some embodiments, a block of electronic circuitrymay be able to perform the Reset Function and place at least a portionof the load 320 in a predefined energized state. The block of electroniccircuitry may be incorporated within the circuit, including, forexample, within the load 320.

Proceeding to FIG. 4, alternative embodiments of a circuit design for anenergized device with a Storage Mode are illustrated, and such circuitsmay be incorporated into Ophthalmic Devices. In some embodiments of thecircuit design 400, the Switching Mechanism 410 may be integrated withinthe power source 405, which then may be placed in the circuit 420 inseries with the load 415. In some alternative embodiments of a circuitdesign 450, the Switching Mechanism 460 may be integrated within theload 465. The load 465 may be placed in the circuit 470 in series withthe power source 455. In these embodiments 400 and 450, the SwitchingMechanism 410 may be responsive to an outside stimulus 425 and 475.

Proceeding to FIG. 5, an embodiment where the primary SwitchingMechanism 550 is a discrete circuit is illustrated. The primarySwitching Mechanism 550 may be comprised of a load 540 separate from thecontrolling load 530 that may operate the energized Ophthalmic Device.In some embodiments, the primary Switching Mechanism 550 may operate ata very low power to constantly sample for the outside stimulus 580. Byutilizing power from the source 510, the primary Switching Mechanism 550may provide benefits over a passive Switching Mechanism, for examplinghaving greater sensitivity or selectivity to external stimulus.

Upon activation by an outside stimulus 580, the switching load 540 maycontrol a switch 520 that may be in the main circuit 570 in series withthe controlling load 530 and the power source 510. In some embodiments,when the main switch 520 is activated, the main circuit 570 may operateat a high power, such as, for example, 3 uA average and 10 mA peak. Insome embodiments, the main switch 520 may further be controlled by theload 540, which may place the switch 520 back in a Storage Mode.

The primary Switching Mechanism 550, in some embodiments, may include anadditional Switching Mechanism 560. This additional Switching Mechanism560 may provide many functions, such as, for example, further reducingcurrent leakage and protecting the power components. In someembodiments, the additional Switching Mechanism 560 may only beactivated once the Media Insert is incorporated in the energizedOphthalmic Device and the device is ready to be packaged. This mayprotect the circuitry from damage that may be caused by subsequentmanufacturing procedures, including, for example, curing lights used toset the hydrogel. In some embodiments, the additional SwitchingMechanism 560 and the primary Switching Mechanism 550 may also beresponsive to different types of outside stimulus 580.

For example, in some embodiments, the additional Switching Mechanism 560may be responsive to temperature, and the primary Switching Mechanism550 may be responsive to ambient light. Such embodiments may allow theenergized Ophthalmic Device to be stored in a cool or cold temperaturewhile in the most conservative stage of a Storage Mode. Once theenergized Ophthalmic Device is exposed to warmer temperatures, theadditional Switching Mechanism 560 may trigger the primary SwitchingMechanism 550 to begin sampling in low power for ambient light, whilestill keeping the main circuit 570 in a Storage Mode. Upon exposure toambient light, the primary Switching Mechanism 550 may close the mainswitch 520 and trigger an Operating Mode.

This combination of temperature and light is for exemplary purposesonly, and it may be apparent to those ordinarily skilled in the art thatother combinations of switching systems may be practical. Thecombination of the primary Switching Mechanism and additional SwitchingMechanism may include, for example, electrical, mechanical, or magneticsystems and may depend on stimuli such as, for example, electromagneticemissions, sound, temperature, or light.

Processes

Proceeding to FIG. 6, a flowchart illustrates exemplary steps that maybe used to manufacture an energized Ophthalmic Device with a StorageMode. At 605, a power source may be incorporated in a Media Insert thatwill be included in an Ophthalmic Device. At 610, a load that mayoperate within an energized Ophthalmic Device may be incorporated in theMedia Insert in a circuit with the power source. At 615, a SwitchingMechanism may be integrated with the circuit incorporated on the MediaInsert. In some embodiments, at 620, a reset function may optionally beintegrated with the circuit.

In embodiments where a load may be incorporated in the Media Insertprior to battery assembly, the reset design may be different from wherethe battery is completed prior to die attachment. For example, where thebattery is completed prior to die attachment, the reset function mayneed to handle a “noisy” connection to the battery, such as, forexample, one with conductive epoxy where the resistance may changeduring curing.

The order of steps 605-620 is for exemplary purposes only, and otherorders and combinations are well within the art described herein. Forexample, in embodiments where the Switching Mechanism is integrated withthe power source, as illustrated in the embodiment 400 in FIG. 4, steps605 and 615 may be combined. In some embodiments, the circuit componentsmay be incorporated in the Media Insert simultaneously.

At 623, the Media Insert with the incorporated circuitry may be includedin the Ophthalmic Device. Optionally, the Media Insert or the OphthalmicDevice may be encapsulated. In some embodiments, step 623 may occurprior to the steps 605-620, wherein the circuit components may beinjected onto the Media Insert after the insert has been encapsulated inthe Ophthalmic Device.

At 625, the energized Media Insert may be placed in a Storage Mode. Theorder of the steps may depend on the overall manufacturing process for aparticular embodiment. For example, in some embodiments, placing thecircuit in a Storage Mode prior to subsequent steps may protect thecircuitry from damage that may be caused by subsequent manufacturingprocedures, including, for example, curing lights used to set thehydrogel. In said embodiments, for example, step 625 may occur prior tostep 623.

At 630 to 645, some embodiments may optionally include an assemblytesting process. The assembly test mode may allow testing of theelectronic circuitry and energized Ophthalmic Device following assemblyof the insert and of the Ophthalmic Device. At 630, the energizedOphthalmic Device may be woken from a Storage Mode by an outsidestimulus. This outside stimulus may be the same or different from theoutside stimulus that may put the Ophthalmic Device in an operating modefor the user. In some embodiments, to allow for exiting a Storage Modeand entering an Operating Mode while still meeting the Storage Modecurrent requirements for use, energy may need to enter the circuitry totrigger the Storage Mode exit.

For example, some embodiments may utilize a photovoltaic device whereina bright light may be incident on the photodetector, for example from aflash light or infrared fiber optic bundle. Sufficient potential mayresult from the exposure to light to close the Switching Mechanism. Withthe Switching Mechanism closed, at 635, the resistance in series withthe load may diminish allowing the Ophthalmic Device to enter anOperating Mode. In embodiments that include a reset function, at 640,exiting a Storage Mode may trigger a power-on reset, as an example, thatmay place the Ophthalmic Device in a known energized state.

At 645, in some embodiments, after a specified startup period toinitialize the digital block and settle the bandgap, regulators, andoscillator, the system may begin sampling the system. Depending on thesystem of activation in the specific embodiment, this sampling may, forexample, build a history of ambient light levels, detect blinks, ordetect the presence of infrared control fiber optic bundles. At 650, theOphthalmic Device may be returned to a Storage Mode until lateractivation by a user. In some embodiments, the assembly test mode may bethe normal Operating Mode with the ability to end the test mode and exitto a Storage Mode. Depending on the embodiment of the device and thespecific method of manufacture, the Ophthalmic Device may be returned toa Storage Mode, for example, through the original means, reversal of theexternal stimulus, or by a new means.

At 655, the Ophthalmic Device may be placed in a sealed package that mayprevent unintentional activation of the Ophthalmic Device from a StorageMode prior to user activation. In some embodiments, such as where aStorage Mode may be sensitive to ambient light, the common blisterpackaging design may need to be modified to include physical attributesthat may prevent the outside stimulus from waking the Ophthalmic Devicefrom a Storage Mode before the user opens the package. For example,where a Storage Mode may be sensitive to ambient light, the packagingmay be impermeable to triggering light. Alternatively, if a Storage Modedepends on the device being held within a specific temperature range,the blister may be comprised of a material that better retains coldtemperature. These blister modifications are for exemplary purposesonly, and it may be obvious to one skilled in the art that othermodifications to packaging may be practical and is well within the artdescribed herein.

Proceeding to FIG. 7, a flowchart illustrates exemplary steps for usingan energized Ophthalmic Device with a Storage Mode. In some embodiments,at 705, a user may open a sealed package, such as a blister, thatcontains an energized Ophthalmic Device in a Storage Mode. At 710, anoutside stimulus may wake the device from a Storage Mode by triggeringthe Switching Mechanism. In some specific embodiments, the user maydirectly trigger the Switching Mechanism, such as, for example, in amechanical system, the outside stimulus may be pressure on the SwitchingMechanism, requiring the user to squeeze or pinch the device.Alternatively, opening the sealed packaging may trigger the SwitchingMechanism without requiring additional action by the user. For example,the outside stimulus may be ambient light.

In some embodiments, such as in FIG. 5, where the Switching Mechanism550 may have an additional switch 560, the energized Ophthalmic Devicemay have multiple levels of Storage Modes. In such embodiments, the usermay trigger multiple levels of activation or, in alternate embodiments,may trigger the final activation step that places the energizedOphthalmic Device in an Operating Mode. Where the user triggers multiplelevels of activation, the process of FIG. 7 may include steps prior tostep 705, such as, for example, removing the sealed package fromrefrigeration, where the additional switch 560 may be responsive totemperature as the outside stimulus.

In some embodiments, at 715, waking the energized Ophthalmic Device froma Storage Mode may minimize the resistance of the Switching Mechanism,allowing the current flow through the circuit to increase to anoperating level. An Operating Mode may be reached after a specifiedstartup period to initialize the digital block and settle a reference,regulators, and oscillator. In embodiments with a reset function, at720, an Operating Mode may prompt the reset function, which may placethe energized Ophthalmic Device in a known energized state. At 725, theuser may place the activated energized Ophthalmic Device on the eye.

In embodiments where the Media Insert is not encapsulated into theOphthalmic Device, the user may not be able to place the OphthalmicDevice directly on the eye. In such embodiments, an additional step, notshown, may be required to use the Ophthalmic Device on the eye. Forexample, in some embodiments, the user may place a soft lens, such as ahydrogel lens, on the eye and then place the energized Ophthalmic Deviceon the soft lens. Alternatively, the user may combine the OphthalmicDevice and the soft lens prior to placement on the eye.

In some embodiments, this step at 725 may occur after a specified timeafter waking the device from a Storage Mode to ensure the device is in aknown state, which may be configured for comfort and safety, asexamples. Once in an Operating mode, in some embodiments, a reference,regulators, core oscillator, and some digital circuitry may becontinuously active. For example, in some embodiments, a photodetectorsystem, including an amplifier and additional digital circuitry, may beactive in repetitive, bursted operation to limit average currentconsumption. The lens driver may be activated depending on systeminputs.

After use, at 730, the user may remove the energized Ophthalmic Devicefrom the eye. In some embodiments, such as with a daily-use lens, theprocess may end with removal of the energized Ophthalmic Device from theeye. In other embodiments where an Ophthalmic Device may be usedmultiple times, further steps may be required. In such embodiments,conserving current leakage during storage periods between usages mayallow for extended power supply life. At 725, a user may return theOphthalmic Device to a Storage Mode. As with the assembly test mode inFIG. 6, a Storage Mode may be reinitiated through various outsidestimuli, including, for example, reversal of the activating stimulus oran independent outside stimulus specific to triggering a Storage Mode.

At 740, the user may store the Ophthalmic Device in an airtightcontainer with a sterilizing solution. During storage, at 743, theOphthalmic Device may optionally be recharged. The order of steps735-743 are for exemplary purposes only and other orders may bepractical. For example, in some embodiments, steps 735 and 740 may becombined wherein placement of the device in the container may initiate aStorage Mode. In a further embodiment, steps 735-743 may be combined sothat placement of the device in the container initiates a Storage Modeand recharges the device. Depending on the specific embodiment, thesterilizing solution may also operate as the outside stimulus, arecharging fluid, or both. In some embodiments, the container mayprovide the outside stimulus, may recharge the power source, or both.

In embodiments that allow for repeated use, at 745, the user may removethe Ophthalmic Device from the storage container. At 750, an outsidestimulus may wake the device from a Storage Mode, and, at 755, theresistance over the Switching Mechanism may decrease to allow currentflow over the circuit to increase to an Operating Mode. In someembodiments, at 760, an Operating Mode may trigger a reset function thatmay place the device in a known energized state. At 765, the user maythen place the energized Ophthalmic Device on the eye. After use, at770, the user may remove the device from the eye. In some embodiments,steps 745-765 may be repetitions of the initial steps 705-725, while inother embodiments, the initial steps 705-725 may be distinct from thesteps 745-765 required for reactivation.

The description of both preferred and alternative embodiments are forexemplary purposes on, and it understood that to those skilled in theart that variation, modification, and alteration may be apparent. It istherefore to be understood that the exemplary embodiments are notlimiting the broadness of the aspects of the underlying invention defineby the claims.

1. A method of manufacturing an energized Ophthalmic Device having an electrical Storage Mode, the method comprising the steps of: incorporating a Media Insert within the energized Ophthalmic Device, wherein the Media Insert comprises an electrical circuit, wherein the electrical circuit comprises an electrical power source, an electrical load, and a first Switching Mechanism, and wherein the first Switching Mechanism comprises a plurality of modes including a first Storage Mode that places the Ophthalmic Device in a predefined low energy consuming state, wherein the first Switching Mechanism adds resistance to restrict current flow through the electrical load while in the first Storage Mode, and an Operating Mode, wherein the first Switching Mechanism allows increased current flow through the electrical load while in the Operating Mode; and placing the first Switching Mechanism in the first Storage Mode.
 2. The method of claim 1 further comprising the steps of: encapsulating the Ophthalmic Device and the Media Insert.
 3. The method of claim 1, wherein the first Switching Mechanism is sensitive to a first stimulus originating external to the energized Ophthalmic Device.
 4. The method of claim 1 further comprising the steps of: testing the operation of the electrical circuit included in the Media Insert before the first Switching Mechanism is placed in the first Storage Mode.
 5. The method of claim 3 further comprising: triggering a first change in mode of the first Switching Mechanism by a first stimulus originating external to the Ophthalmic Device, wherein the first change places the first Switching Mechanism in the Operating Mode; stabilizing current flow at an operating level; testing the operation of the electrical circuit included in the Media Insert while the first Switching Mechanism is in the Operating Mode; returning the first Switching Mechanism to the first Storage Mode.
 6. The method of claim 5 wherein the returning of the first Switching Mechanism to the first Storage Mode is controlled by a first component of the electrical circuit.
 7. The method of claim 1, wherein the electrical circuit further comprises a first block of electronic circuitry able to perform a first Reset Function upon a first portion of the electrical load, wherein the first block is comprised within the electrical circuit and, when activated, places the portion of the electrical load in a first predefined energized state.
 8. The method of claim 5 further comprising the steps of activating the first Reset Function when the current flow increases to the operating level, wherein the electrical circuit further comprises the first block of electronic circuitry able to perform the first Reset Function upon the portion of the electrical load, wherein the block is comprised within the electrical circuit and, when activated, places the first portion of the electrical load in the first predefined energized state.
 9. The method of claim 1, wherein the placement of the first Switching Mechanism in the first Storage Mode occurs prior to incorporating the Media Insert within the energized Ophthalmic Device to protect components within the electrical circuit.
 10. The method of claim 1 further comprising: packaging said energized Ophthalmic Device in a sealed container.
 11. The method of claim 9, wherein the sealed container comprises a physical attribute to maintain the first Storage Mode.
 12. A method of using the energized Ophthalmic Device having the first Storage Mode, the method comprising the steps of: opening the sealed container, wherein the sealed container holds at least the energized Ophthalmic Device with the first Storage Mode; and triggering a second change in mode of the first Switching Mechanism through the second stimulus originating external to the Ophthalmic Device, wherein the second change in mode reduces resistance of the first Switching Mechanism.
 13. The method of claim 12, further comprising the steps of: placing the energized Ophthalmic Device on an eye.
 14. The method of claim 12 further comprising the steps of: activating a second block of circuitry to perform a second Reset Function when the current flow through the electrical circuit rises to a specified level above the Storage Mode level, wherein the second Reset Function results in placement of the Ophthalmic Device in a second predefined energized state.
 15. The method of claim 14, wherein the second predefined energized state is optimized for initial use of the Ophthalmic Device and placement upon the eye.
 16. The method of claim 13 further comprising the steps of: removing the energized Ophthalmic Device from the eye; triggering a third change in mode of the first Switching Mechanism, wherein the third change in mode returns the Ophthalmic Device to the first Storage Mode by increasing resistance of the first Switching Mechanism; storing said energized Ophthalmic Device in a sealable container with at least a sterilizing means; removing the energized Ophthalmic Device from the sealable container; triggering a third change in mode of the first Switching Mechanism through a third stimulus originating outside of the Ophthalmic Device, wherein the third change in mode reduces resistance of the first Switching Mechanism; and placing the energized Ophthalmic Device on the eye.
 17. The method of claim 16, wherein the returning of the first Switching Mechanism to the Storage Mode is controlled by a second component of the electrical circuit.
 18. The method of claim 17, wherein the second component further comprises a sensor sensitive to a fourth stimulus originating external to the energized Ophthalmic Device.
 19. The method of claim 13, wherein the first Switching Mechanism is a first single-use Switching Mechanism, and the method further comprises the steps of: removing the energized Ophthalmic Device from the eye; triggering a first change in mode of a second single-use Switching Mechanism, wherein the first change in mode of the second single-use Switching Mechanism returns the Ophthalmic Device to the first Storage Mode by increasing resistance of the second single-use Switching Mechanism; storing said energized Ophthalmic Device in the sealable container with at least the sterilizing means; removing the energized Ophthalmic Device from the sealable container; triggering a second change in mode of the second single-use Switching Mechanism through a fourth stimulus originating external to the Ophthalmic Device, wherein the second change in mode of the second single-use Switching Mechanism reduces resistance of the second single-use Switching Mechanism; and placing the energized Ophthalmic Device on the eye.
 20. The method of claim 12, wherein the electrical circuit further comprises a second Switching Mechanism, and wherein the method further comprises the steps of: exposing the sealed container to a fifth stimulus originating external to the Ophthalmic Device, wherein the exposure triggers a change in mode of the second Switching Mechanism and places the Ophthalmic Device in a second Storage Mode.
 21. The method of claim 20, wherein the second Storage Mode is a low energy consumption state and allows the first Switching Mechanism to begin sampling for the second stimulus.
 22. A method of using the energized Ophthalmic Device having the first Storage Mode, the method comprising the steps of: opening the sealed container, wherein the sealed container holds at least the energized Ophthalmic Device with the first Storage Mode; triggering the second change in mode of the first Switching Mechanism through the second stimulus originating external to the Ophthalmic Device, wherein the second change in mode reduces resistance of the first Switching Mechanism; placing a soft ophthalmic lens on the eye; and placing the energized Ophthalmic Device adjacent to the soft ophthalmic lens. 